Most of the world's dictators share a common fear, and it's not of the United States, NATO, the United Nations or any outside entity. No, the force that most threatens them is social media.

Originally designed as enhanced online chat forums for young Americans, Facebook, Twitter, blogs and the rest have spread around the world and are now being used as cudgels against authoritarian leaders in places like Vietnam, Russia, Belarus and Bahrain. In those states and so many others, the leaders are attacking tweeters and bloggers as if they were armed revolutionaries. And the repression is spreading.

In India a few days ago, a 21-year-old medical student posted a mildly critical comment about a Hindu political figure who'd just died. Within 24 hours, police arrested her and a friend who had "liked" the student's Facebook post and charged them with engaging in hateful, offensive speech - this in one of the world's strongest democracies. (Police let them go a few days later.)

A more typical example comes from Belarus. There, President Alexander Lukashenko, commonly known as Europe's last dictator, seems to be fighting online verbiage all the time.

Recently, Ecuador's Supreme Court turned down an extradition request from Belarus for a blogger who fled there after the government charged him with fraud. Alexander Barankov had been blogging about widespread government corruption. That particular extradition denial stands as a bold demonstration of the fraud charge's absurdity because Rafael Correa, Ecuador's president and an acolyte of Venezuelan President Hugo Chavez, is no champion of press freedom. Far from it. And yet he defied the Belarus request.

Barankov is hardly the only example. The Organization for Security and Cooperation in Europe declaimed Lukashenko's record of arresting journalists and bloggers, saying "unfortunately recent detentions and searches in Minsk and elsewhere in the country show continued efforts to muzzle dissenting voices and clamp down on freedom of expression online."

Iran, not surprisingly, is even tougher. Bloggers are given long prison terms or sentenced to death, charged with "enmity against God" and subverting national security. Human-rights groups say the bloggers and tweeters are tortured in jail. In mid-November, one died in police custody for unexplained reasons.

Iran actually is trying to set up its own internal Internet. There, the government says, "unregulated social media and other content likely to encourage dissent" simply won't be available.

But the sad truth is, the dictators whose people are the most repressed - locked in abject poverty - don't have to worry about the social-media problem. In Laos, Cambodia, Eritrea, Mozambique and a handful of other states, most people have no access to computers or cell phones. Many of them are illiterate and couldn't use the devices even if they had them. That leaves their leaders to trample over their rights with near-impunity.

China demonstrates this better than any nation. The state's economic-development program pulled millions of Chinese out of poverty. Previously, Chinese were relatively quiescent. But with prosperity came a new understanding of how venal and repressive the Chinese Communist Party really is. So, millions of Chinese took to new social-media platforms to complain.

Now China spends more money on internal security - including a massive online censorship office - than it does on its military. Persistent online critics are imprisoned or worse. That demonstrates a clear fact: The Chinese government fears its own people far more than it does any outside power.

Other states are catching up. Russia is implementing a massive new online Internet filtering system, ostensibly to protect children from offensive sites. But human-rights advocates warn that it can just as easily be used to block social-media commentary the government doesn't like.

In Oman this fall, six people were jailed for defaming the state on Facebook. That came after the National Human Rights Commission of Oman (an oxymoron if I've ever heard one) labeled those posts and others "negative writings that violate Islamic principles."

Nearby, Bahrain is trying to have it both ways. On the one hand, it jailed a human-rights advocate for tweeting criticism of the nation's tyrannical prime minister. Then authorities arrested four more Bahrainis for Twitter posts considered to be critical of the king.

At the same time, though, the government allowed one of the state's biggest companies, a telecom provider named Zain Bahrain, to sponsor a major business conference there, undoubtedly because it will be quite profitable for the island's hotels, restaurants and other travel-related businesses.

What was the conference about? Its title: The Social Media Masters Forum.